The four-part calcaneal fracture classification most likely refers to the Sander's CT Classification. In English these are commonly called Types 1-4, but if you are looking for a more descriptive category, I would write

Type 3 - Three-part fracture (split/depression)

If you want really to split the hair, a "fracture en soufflet" is technically more of a "joint-depression fracture" (vertical) than a "tongue type fracture" (horizontal), but those are both types of the Type 3 fracture, so for the purpose of this context, I would go with the more general sense of the word. Good luck!